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Connecting two systems to one subwoofer?

dshreter

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I have two systems in one room and am trying to determine if I could safely connect both systems to the same subwoofer without too much trouble.
  • One system has a Sonos AMP serving electronic duties for a TV
  • The other is a desktop system with a Motu M2 connected to KH80 active monitors
  • Realistically I don't use the two systems simultaneously, but it's possible they would both get turned on and this should not blow up any components
I can set volume / gain on the sub, the Sonos sub output, and also the KH80 monitors, so the theory is I could get both systems dialed in at least from a volume perspective. EQ would have to be set preferentially for one system, I'm aware it won't be "perfect" for both.

Is setting up per the diagram below valid? Is this safe for all of the electronics?

double sub.png
 

DVDdoug

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Don't "short" the left & right outputs together! You can use one or the other. Bass is usually mono anyway (identical in both channels).

If you know how to solder you can make a passive mixer with two 10K resistors (or a two pair for a stereo mixer). It will reduce each "mixed" signal in half (-6dB) and since you're not actually mixing, that's a -6dB loss.

Or you can get a little mixer for $100 or less.
 
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dshreter

dshreter

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Don't "short" the left & right outputs together! You can use one or the other. Bass is usually mono anyway (identical in both channels).

If you know how to solder you can make a passive mixer with two 10K resistors (or a two pair for a stereo mixer). It will reduce each "mixed" signal in half (-6dB) and since you're not actually mixing, that's a -6dB loss.

Or you can get a little mixer for $100 or less.
Thanks. So if I want to retain both channels on the Motu I should use something like this otherwise just take on channel and call it "good enough"
 

AdamG

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I have two systems in one room and am trying to determine if I could safely connect both systems to the same subwoofer without too much trouble.
  • One system has a Sonos AMP serving electronic duties for a TV
  • The other is a desktop system with a Motu M2 connected to KH80 active monitors
  • Realistically I don't use the two systems simultaneously, but it's possible they would both get turned on and this should not blow up any components
I can set volume / gain on the sub, the Sonos sub output, and also the KH80 monitors, so the theory is I could get both systems dialed in at least from a volume perspective. EQ would have to be set preferentially for one system, I'm aware it won't be "perfect" for both.

Is setting up per the diagram below valid? Is this safe for all of the electronics?

View attachment 227441
SVS is very good about answering technical questions. My advice is to ask them before you do anything.

https://www.svsound.com/pages/customer-service
 

Speedskater

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You can connect two line level outputs together by following this old Rane Note:

Why Not Wye?
Dennis Bohn, Rane Corporation
RaneNote 109 written 1991; last revised 4/04

Splitting Signals
Subwoofing in Mono
Unbalanced Summing
Balanced Summing
Output Impedances

 
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